There are on the whole two types of architecture for fuel cells:                filter press architecture comprises stacking a plurality of fuel cell cores. Said first architecture is generally preferred where high-power uses are involved.        alternatively, planar architecture comprises juxtaposing a plurality of fuel cell cores in the same plane. Said second implementation is, for its part, preferred for low-power uses of the nomad or portable type. It is to this type of architecture that the present invention applies.        
Planar architecture uses in the main two fabrication technologies:
The first technology comprises using an electrode—membrane—commercial electrode (cell core) assembly deposited onto a substrate that is permeable by means of a porous material, as disclosed for example in U.S. Pat. No. 5,759,712.
The second technology comprises using another type of permeable substrate as cell core support, as disclosed in the publication by J. S. Wainright et al. <<Microfabricated fuel cell>>, Electrochimica Acta, Volume 48 (2003), Pages 2869-77.
Said cell core 1 is fabricated by stacking successive layers of materials constituting said core (current collectors 10, active layers 11 and membrane), as shown in FIG. 1. As set forth in this figure, the permeable substrate 2 is made out of silicon, and is engraved with channels 4 to allow the hydrogen to reach the cell core 1.
Thus, on a single substrate 2 a plurality of cell cores 1 can be fabricated which, when put in series, provide a generator that has the required electrical characteristics (cf. FIG. 2). Indeed and in said design, the number of cell cores defines the system voltage, and the surface of the cell cores defines the available current.
Said cell, once produced, needs to be integrated into a “packaging”, to allow a “connection” with the fuel. Said “packaging” 3, shown in FIG. 2, is connected to a cartridge constituting a fuel tank, thereby allowing the cell anode to be supplied with fuel. Furthermore, it ensures the impermeability of the system. Said “packaging” therefore constitutes a protective cover, which may take the form of a detachable and sealed cap.
As a consequence, two “inert” materials are used when fabricating a fuel cell of this kind: that constituting the substrate 2 or support for the cell cores 1, and that constituting the “packaging” 3. Their integration in the fuel cell involves additional cutting and assembly stages, which make said embodiment relatively unattractive.
There is therefore a need to develop new planar fuel cell designs, for which the method of fabrication is more straightforward and faster to implement.